Electronic circuit devices usually consist of several components having selected surfaces between the components defining intended electrical and thermal interfaces. Such components typically include an IC (integrated circuit) or hybrid substrate having a plurality of contact pads, a lead frame having a like plurality of leads, and a heat sink. During assembly, the substrate, heat sink, and lead frame are typically pressed together at a selected compression in an assembly fixture, with each of the leads aligned with and contacting its associated contact pad via a corresponding solder layer and with the heat sink aligned with and contacting the substrate via a solder layer, and heated at a high tempeature to flow the solder. Because of the differential in the coefficients of thermal expansion between the several components and between the different components of the assembly fixture, as well as high temperature induced component warping, among other things, it often happens however that the selected compression either over-compresses or under-compresses the thermal and electrical interfaces. In the former case the components are over-compressed, which squeezes the solder out from between the electrical interfaces producing electrical shorts between adjacent leads, and which squeezes the solder out from between the thermal interface producing an undesirable bond. In the latter case the components are under-compressed, which due to the surface tension of the solder, causes it to form into solder balls in the electrical interfaces both producing electrically open or weak bonds and entrapping gas, and likewise producing an undesirably high resistance path and entrapping gas or flux at the thermal interface.